<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<script type="text/javascript">
			//赋值给变量什么类型，就是什么类型
			var num;
			console.log(num);
//			typeof()打印类型
			console.log(typeof(num));
			
//			null是赋值的
			num = null;
			console.log(num);
//			object类型
			console.log(typeof(num));
			//字符串类型
			num = "JS!"
			console.log(typeof(num));
			console.log(num);
			
			
			//关系判断
			var m = "3";
			var n = 3;
			//值相等
			if(m == n){
				console.log("m == n");
			}
			//类型不相等
			if(m === n){
				console.log("m === n");
			}
		</script>
	</head>
	<body>
		
	</body>
</html>
